Treating printed paper to remove the ink and recover the pulp.



HORACE M. BELL AND EDMUND R. LAPE,' 0F SWANTON, VERMONT.

TREATTNG PRINTED PAPER TO REMOVE THE INK AND RECOVER THE PULP.

masses. Ho Drawing.

To all whom it may concern EDMUND R. LAPE, citizens of the United States, residing at Swanton, in the county of Franklin and State of Vermont, have invented new and useful Improvements in Treating Printed Paper to Remove the Ink and Recover the Pulp, of which the following is a specification.

factured from old newspapers, magazines, and other similar printed paper, but ow ng to the apparent impossibility of removlng the printers ink and other coloring matter from the stock, the new pulp is more or less discolored, and hence the paper produced therefrom is unfit for use except as boxboard, wrapping paper, mailing tubes, and the like. \Ve have found that in the well known methods now employed in removmg the ink. from the old paper stock, it is customary to beat, the stock into a pulpy mass while being treated with the ink-removing agent. This method while effecting the separation of a very large percentage of the ink from the paper, causes quite a large proportion of the carbon particles of the ink, which are in suspension in the liquid, to be worked into the paper fibers so that the latter are thoroughly impregnated with the coloring matter. After the ink has been worked into the fibers in this manner it is impossible to effect its removal, and this condition is responsible for the discoloration of the pulp made from old paper stock.

One of the objects of our invention is to so treat the waste paper stock as to thoroughly remove the ink and other coloring matter therefrom and to prevent it from being embedded in the paper pulp, whereby a pure white paper pulp may be produced.

A further object of the invention is to so treat the waste paper stock as to effectually remove the ink and other coloring matter therefrom with practically no loss of the.

stock.

In the practice of our method, the waste paper stock is first cleansed or dusted in any suitable or preferred manner, and then torn or cut by any suitable means, into small pieces or sheets. The size of the pieces is immaterial except that they must not be so small as to be destroyed in the next step of the process. The stock after being torn or cut in the manner referred to is then placed in a suitable receptacle and subjected to the Specification of Letters Patent.

Heretofore paper pulp has been manu- Patented Mar. 2, tars.

Application flledJune 20, 1914. Serial No. 846,262.

action of a soap solution made from any preferred soap. The strength of the soap solution may vary and we do not desire to limit ourselves to any fixed proportion of the ingredients thereof. We have obtained excellent results, however, by employing the following proportions, to wit ;one part of soap and six hundred parts of water to ten parts of the paper stock. lVe have found that the ink may be removed by the use of either hot, cold, or boiling Water in the soap solution, and we accordingly desire it to be understood that our method contemplates the use of soap and Water, irrespectitge of i the temperature of the water which may be varied to suit conditions. While in contact with the soap solution the small pieces of paper stock are agitated sufficiently to cause every part ofthe paper to come into contact with the solution, and also to cause the faces of the pieces of paper to rub against'each other and' against the tank containing the same, thereby producing sufficient friction or attrition to assist the action of the soap solution in loosening the ink from the pieces of paper. lare must be taken, however, in the agitation of the paper, not to break up the pieces or to cause such an action as will tend to drive the ink particles into the paper fibers. The object of the step thus described is to remove as much of the ink from the surface of the paper as possible, without disintegration of the paper, and to cause the ink particles to remain suspended in the soap solution. As a result of this treatment the printed matter is practically removed from the small sheets of paper, and the soap solution with the ink particles suspended therein may be drawn off and used again. In the treatment of some classes of magazine paper it may be desirable to add a small percentage of a suitable alkali to the soap solution, although ordinarily this is unnecessary. After treatment with the soap solution, the material is washed in clear water,

ing is that the paper stock is in small pieces and the ink particles are very finely divided, and hence easily separated in the Washing. If the paper, after Washing, is found to bear slight impressions of rint, more soapsolution may be added-t0 the beater when the material is transferred thereto for the purpose of pulping. The soap solution'in the beater Will effectually remove all trace of ink and the resultant pulp will be White and perfectly suitable for use in the ordinary manner, with practically no loss of material. It is obvious that if desired, the soap solution With the ink particles suspended therein, may be treated to recover the-ink."

We claim as our invention 1. A process of treating printed paper stock to remove the ink and recover the pulp, comprising subjecting small sheets or pieces of the printed paper to the action of a soap solution and 'eflecting removal of the ink by continuously subjecting the stock during the action of the soap solution, to an agitation suflicient to practically rub the ink off the surfaces of the sheets or pieces and insuflicient to materially disintegrate the stock, Washing the stock so treated, and finally pulping,

2. A process of treating printed paper stock to remove the ink and recover the pulp, comprising subjecting small sheets or pieces of the printed paper to the action of a soap solution and effecting removal of the ink by continuously subjecting the stock during the action of the soap solution to an agitation sufficient to practically rub the ink off the surfaces of the sheets or, pieces and insufficient to materially disintegrate the stock, subjecting the stock to a series of Washing operations, and finally pulping.

3. A process of treating printed paper stock to remove the ink and recover the pulp, comprising subjecting small sheets or pieces of the printed paper to the action of a soap solution and effecting removal of the ink by continuously subjecting the stock during the action of the soap solution. to an agitation sufficient to practically rub the ink ofl' the surfaces of the sheets or pieces and insufiicient to materially disintegrate the stock, Washing the stock and again agitating the same, and finally pulping.

l. A process of treating printed paper stock to remove the ink and recover the pulp, comprising subjecting small sheets or pieces of the printed paper to the action of a soap solution and effecting removal of the ink bv continuously subjecting the stock during the action of the soap solution, to an agitation suflicient to practically rub the ink off the surfaces of the sheets or pieces and insuflicient to materially disintegrate the stock, Washing the stock, beating up the Washed stock to form a pulp, and subjecting the stock to the action of a second soap solution during the beating operation.

In testimony whereof We have hereunto set our hands in presence of tWo subscribing Witnesses.

HORAGE M. BELL. EDMUND R. Lars.

lVitnesses:

B. (J. SHELDON, W. G. CARMAN. 

